Compound cylinder



Dec. 26, 1939.

A. A. LowEKE coMPoUND CYLINDER Filed zsept.' 2e. 195s 2 Sheets-Sheet l f wm wm mm www No R W f, m w g om Q\\ QM W mh.

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neg. ze; 1939.

A. A. LowEKE coMPoUND CYLINDER- Fil'ed sept. 26. 193sl 2 Sheets-Sheet 2 rIll/Ill Ihlln.

INVENTOR.

ATTORNEY.

and a plurality of spaced ports I8 in the wall of the sleeve provide communications between the interior of the sleeve and the annular chamber.

A piston head 80 threaded on the sleeve 10 is fitted for reciprocation in the large chamber 36 of the cylinder. This head has a plurality of passages 82 therethrough providing communications between the annular chamber 16 and that portion of the cylinder forward of the piston head 80. The head 80 has a concentric extension 84, and a passage 86 extending through the extension and the head provides a communication between the sleeve 10 and that portion of the cylinder forward of the head 80. A ball valve 88 in the sleeve 'l0 controls the passage 80, and a collapsible leak-proof'cup 90 sleeved on the extension and seated on the head 80 controls the passages 82. A spring 92 interposed between a spring seat in the bottom of the cup 90 and the head 40 of the cylinder serves to retain the cup 90 `against displacement and also to return the piston to its retracted position.

A piston 94 reciprocable in the sleeve 'I0 includes a head 96, a skirt 98, and a concentric extension |00 having on its free end a knob |02. The head 96 and the extension |00 have an axial passage |04, and the knob |02 has a plurality of diametral passages |06 communicating with the axial passage. The passages |04 and |06 provide communications between the interior of the skirt 98 of the piston 94 and that portion of the sleeve 10 forward of the piston 94. A leak-proof cup |08 sleeved on the extension |00 and seated on the head of the piston 94 inhibits the seepage of fluid past the piston. The cup |08 is held against displacement by the knob |02 which also serves to actuate the ball valve 90.

A ball valve ||0 in the skirt of the piston 94 controls the passages |04 and |06. This valve is urged to its closed position by a spring ||2 interposed between the ball and a shell ||4 slidable in the skirt of the piston. The shell isadjustably supported on a tube ||6 threaded in that portion of the sleeve 10 having the smaller diameter. The spring ||2 also serves to urge the piston to actuate the ball valve into closed position.

Suitably arranged in the reservoir adjacent its top are 4oppositely disposed bosses ||8 and |20 transversely bored for the reception of an operating shaft |22. As shown, the shaft has a double diameter, and that portion having the smaller diameter is threaded for the reception of a lever or an actuator |24 arranged for the actuation of the piston 58 and the valve 26. When the actuator is in the position of rest, the valve 26 is retained in open posi.ion so that'fiuid may return from the motors through the fluid pressure delivery pipe 54 to the reservoir. Suitable means, such as a leak-proof washer |26 sleeved on the shaft, is provided to inhibit the seepage of fluid from the reservoir past the shaft, and the shaft is suitably knurled as at |28 for the reception of an operating lever |30. l

Assuming that the device is properly connected in the system and that the system is filled with suitable liquid or uid, by applying force to the operating shaft |22, the actuator |24 is moved from the stop 30, resulting in releasing the valve 26, whereupon the valve moves to its closed positii. This movement of the actuator also applies force to the piston 56. During the initial movement of the piston on its compression stroke, uid pressure is received on the piston head 80, and iiuid is drawn past the piston 58 and the collapsible leak-proof cup 12 into the cylinder forward of the piston 58.

Upon attaining a predetermined pressure by this movement of the piston 56, the ball valve 83 is urged by the pressure on the fluid in the large chamber 36 from its seat to open the passage 86. As the valve 88 opens, the pressure on the cup 90 is relieved, and the pressure is equalized on both sides of the piston head 80.

The pressure is then received by the cup 'l2 onY the piston 58, also on the cup |08 on the piston 94 and on the ball valve H0. This transfer of pressure is effected without loss; Upon further movement of the piston and upon attaining a second predetermined pressure, the ball valve H0 is opened by the pressure on the uid in the cylinder forward of the piston 58 to permit the fluid to flow through the passages |04 and |06, the skirt of the piston, the tube ||6 and passages 62 and 64 and the circumferential groove 60 and past the body of the piston 58 to the reservoir.

As the piston moves on its retraction stroke, the valve 44 closes and retains the iiuid in the system underpressure. This pressure is released.

when the actuator is moved to its retracted position against the stop 30, in which position the actuator moves the pin 28 to trip the valve 26 so that any exces's fluid in the system may be returned to the reservoir. As the piston moves to its retracted position, the cups l2 and 90 collapse, and fluid is drawn from the reservoir, past the cups into the cylinder so as to completely ll the cylinder for subsequent operation.

In a normal operation, the valve 26 isY closed so that uid surges back and forth through the uid pressure delivery line or conduit 46 connected between the fluid pressure producing device and the fiuid pressure actuated motors 48.

' As shown, when the actuator is moved to its retracted position, the valve 44 is closed and the valve 26 is tripped so that excess fluid in the system may be returned to the'reservoir.

Although this invention has been described in connection with certain specific embodiments, the principles involved are susceptible of numerous other applications that may readily occur to persons skilled in the art. The invention is, therefore, to be limited only as indicated by the scope of the appended claims. l

Having thus described the various features of the invention, what I claim as new and desire to secure by Letters Patent is,-

1. A fluid pressure producing device comprising means for producing pressure including spaced pistons each having an orifice, a sleeve connecting the pistons and communicating with the orifices, fluid pressure actuated means in the sleeve for controlling the orifices operative at a predetermined pressure to open the orifice in one of the heads and at a greater pressure to open the orifice in the other head, and means for adjusting the fluid pressure actuated means for opening operation at the pressures determined.

2. A fluid pressure producing device comprising means for producing pressure including spaced pi tons each having an orifice, a sleeve connecti g the pistons, a valve controlling the orifice in one of the pistons, means movable in the sleeve for control of the valve, said means having a passage therethrough, a valve controlling the passage, a spring in the sleeve urging the valves to close the'orifices and the passage, and means for adjusting the load on the spring.

3. A fluid pressure producing device comprisinga double diametral cylinder, a piston movable CAB aisaeox therein, said piston having-spaced heads each provided with an orifice, one movable in that portion of thacylinder having the smaller diameter and the ther movable in that portion of the cylinder having the larger diameter, a sleeve connecting the heads and communicating with the orices, pressure actuated k'means in the sleeve for controlling'the orifices operative ata predetermined pressure to'open one 'i the orliices and at a greater pressure to open the other orice, and means for adjusting the pressure actuated means for opening operation at the pressures de-` j termined.

4.` A iiuidpressure producing device con'ipris-` ing a piston having an orifice, a. sleeve on the piston communicatingwith the oriiice, a piston on the sieeve'havins an orice communicating with the sleeve, valves in the sleeve for controlling'theoriiices, means normally holding the cesslvely in response to predetermined pressures,

4and means icor` adjusting the opening operationthereof to open the valves ais-the predetermined s pressures. v .a v

5. A iluid pressure device comprising a piston having a passage therethrough, a doublediametral 'sleeve supported on the head oi the piston in communication with the passage, a head on the sleeve having an oriiice communicating with the sleeve, a valve in the sleeve controlling the orifice, a piston movable in the sleeve having a passage therethrough, a valve controlling the passage, a tension member in the sleeve urging the valves to close the orlices and the passage, and means for regulating the load on the tension member.

. AARON A. LOWIKE.

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valves closed operative to'open the valves suci l 

